I. Field of the Invention
This invention relates generally to a portable, hand-held apparatus for equalizing pressure in the middle ear, and more particularly to a device of the type described that provides improved control over the air pressure applied by the device to a patient's Eustachian tubes during a treatment procedure.
II. Discussion of the Prior Art
In U.S. Pat. Nos. 5,419,762 and 5,885,242 to Arick, et al. (the contents of which are hereby incorporated by reference), there is described an apparatus for facilitating the Politzer maneuver for equalizing the pressure in the middle ear in patients suffering from Eustachian Tube Dysfunction (ETD) or Aerotitis Media. That apparatus comprises an electric-powered air source contained in a hand-held housing for providing a continuous flow of air to an exit port of the device. More particularly, a battery-powered DC motor, when energized, drives a small pump or compressor whose outlet is connected by a short length of plastic tubing contained in the housing to the device's exit port in a nozzle projecting from the housing and that is adapted to seal against one of the patient's nostrils. With the continuous flow of air into one nostril and with the other nostril pinched closed, the patient is asked to swallow. Swallowing closes the esophagus and directs air pressure to the Eustachian tube, opening it to allow any fluid to flow from the middle ear and/or to restore pressure balance to the middle ear.
The Arick, et al. '242 patent suggests that the applied pressure generated by the pump be limited to a lower pressure of about 1.5 psi for infants and small children and a higher pressure of about 3 psi for adults. For this purpose, a speed control circuit is coupled between the battery and the motor terminals. It has been found, however, that attempting to accurately regulate the pressure of the output air by controlling motor pump speed is less than satisfactory. Those skilled in the art recognize that the motor speed, and thus the pump's air flow rate is dependent on battery voltage and that battery voltage varies with the depletion state of the battery's charge as well as with temperature. One can understand, therefore, that the desired airflow rate, measured in liters-per-minute and in air pressure measured in pounds-per-square-inch that can be developed in a given time using the selector switch 20a in FIG. 7 of the '242 patent, may be difficult to maintain.
It is accordingly a principal object of the present invention to provide an improved apparatus for affecting the Politzer maneuver.
Another object of the invention is to provide a hand-held, battery-operated device containing a motor-driven pump for producing a continuous flow of air at the device outlet nozzle at a plurality of selectable pressure values that are independent of battery state over the expected life of the battery.